Multi-mode methods and devices utlizing battery power level for selection of the modes

ABSTRACT

Disclosed are a methods and devices in a battery-powered multimode wireless communication device ( 102 ) that operates pursuant to first and second communication protocols in idle and active modes. The battery power level is monitored and may drop to a predetermined threshold while operating pursuant to the first communication protocol. The device switches from the first wireless communication protocol so that the device is operating in accordance with the second communication protocol in the event that the battery power level has dropped to the predetermined threshold while operating pursuant to the first communication protocol in idle mode or in active mode.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to wireless communications, andmore particularly to switching between modes in multi-mode wirelesscommunication devices based different criteria, for example, based on abattery power level and/or the cost of service.

BACKGROUND

Mobile communication devices, such as battery powered cellulartelephones, can be equipped with multiple transceivers. In addition tocommunicating pursuant to traditional communication protocols such asCDMA and GSM, mobile communication devices can also communicate pursuantto non-cellular protocols. For example, mobile communication devices areoften enabled with a Bluetooth transceiver. For communication pursuantto Wireless Fidelity (WIFI) or wireless local area network (WLAN)protocols, mobile communication devices can be equipped with a WIFItransceiver in addition to their CDMA and GSM transceivers.

Dual-mode communication devices can leverage the ubiquity of cellularnetworks (GSM and CDMA) with the high performance and low operationalcosts of local-area WIFI networks. The dual-mode roaming capabilityallows wireless handsets to utilize cellular or WIFI networks to placeand receive calls, and to provide Internet access for email and Websurfing while the device is in an active mode (in call).

The various aspects, features and advantages of the disclosure willbecome more fully apparent to those having ordinary skill in the artupon careful consideration of the following Detailed Description thereofwith the accompanying drawings described below. The drawings may havebeen simplified for clarity and are not necessarily drawn to scale.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a wireless communication system.

FIG. 2 is a flow chart illustrating the operation of a mobilecommunication device in idle mode.

FIG. 3 is a flow chart illustrating the operation of a mobilecommunication device in active mode.

FIG. 4 is a signal flow diagram of a mobile communication device in idlemode operating pursuant to a WIFI protocol.

FIG. 5 is a signal flow diagram of a mobile communication device inactive mode operating pursuant to a cellular communication protocol.

DETAILED DESCRIPTION

In one embodiment, a battery-powered multimode wireless communicationdevice that operates pursuant to a first and second communication modeswitches from the first active communication mode so that the deviceoperates to the second active communication mode in the event thatbattery power level drops to a predetermined threshold while operatingpursuant in the first active communication mode. In one embodiment, thedevice switches from operation on a cellular communication protocolwhile in a call to operation on a wireless local area network protocolin the event that the battery power level drops to the predeterminedthreshold. The wireless communication device may also perform partialswitch the operation of certain functions to the other transceiver. Forexample, a video stream could be handed over from a first transceiver toanother transceiver and voice call could be maintained on the firsttransceiver.

The switching process can be transparent to the user. Alternatively, thedevice may prompt the user with a request for instructions so that theuser may choose to switch from one mode to the other. In someapplications, an emergency call takes priority over any benefits thatmay be obtained by switching protocols, and thus in these embodimentsthere is no switching between protocols during the emergency call. Anemergency call can be identified, for example, by the telephone numberinput to the mobile communication device.

In another embodiment, the device hands off a function performed on thewireless communication device to an external device wherein the externaldevice performs the function performed on the wireless communicationdevice. For example, the device could connect to an external audiodevice, e.g., sound system, or to an external video system, e.g., alaptop or external monitor, using a Bluetooth or through InternetProtocol connection when the battery threshold is reached, thus reducingpower consumption associated with performing the function on thewireless communication device.

FIG. 1 illustrates a mobile communication device, some of its componentsand two networks that operate pursuant to different communicationprotocols. More than two different communication protocols are withinthe scope of this discussion as well. The device 102 can have a display104, an antenna 106, a keypad for input 108 and a battery usability icon110 on the display. The mobile communication device 102 represents awide variety of communication devices that have been developed for usewithin various networks. Such handheld communication devices include,for example, cellular telephones, messaging devices, mobile telephones,personal digital assistants (PDAs), notebook or laptop computersincorporating communication modems, mobile data terminals, applicationspecific gaming devices, video gaming devices incorporating wirelessmodems, and the like. Any of these portable wireless communicationdevices may be referred to as a mobile station or user equipment. It isunderstood that any and all mobile wireless communication devices arewithin the scope of this discussion.

FIG. 1 depicts the mobile communication device 102 configured tocommunicate with two networks, a cellular network 112 and a WIFI networkthrough its access point 114. The networks typically communicate inaccordance with different communication protocols. The cellular networkprotocol may be for example, CDMA, GSM, and/or W-CDMA or some othercellular communication protocol. Exemplary WIFI network protocolsinclude, but are not limited to, IEEE 802.11/802.16. Other protocols arewithin the scope of this disclosure. A multi-mode mobile communicationdevice may include a plurality of transceivers for receiving andtransmitting pursuant to the different protocols. A first transceiverfor communication pursuant to a first protocol 116 and a secondtransceiver for communication pursuant to a second protocol 118 areshown. In other embodiments, the first and second transceivers could bedifferent incarnations of a single transceiver, for example, asoftware-defined radio transceiver. In this disclosure the terms “firstprotocol” and “second protocol” are used interchangeably. It is clearfrom the context whether the first protocol refers to, for example, aWIFI protocol, and the second protocol refers to, for example, cellularprotocol. It is also understood that the mobile device may communicatevia more than two transceivers.

The mobile communication device is further configured with a processor120, memory 122 and a power source 124, such as a battery. Instructionmodules 126 can include instructions that are in hardware and/orsoftware. The operations of the instruction modules will be described indetail in reference to the flow charts and signal flow diagramsdiscussed below. Briefly, the modules can include a battery power leveldetermination module 128 coupled to the battery and a switching module130 that switches the device 102 from operation via the firstcommunication protocol transceiver 116 to operation via the secondcommunication protocol transceiver 118, for example, in the event thatthe battery power level drops to a predetermined threshold whileoperating via the first communication transceiver. The modules canfurther include a searching module 132 for searching for service on adifferent network in the event that the battery power level drops to thepredetermined threshold. The modules can further include an emergencycall determination module 134 for determining whether the device is inan emergency call activation state, and a switch avoidance module 136operable for when the device is in an emergency call activation state toavoid breaking emergency communication.

A dual or multi-mode device 102 may operate in either idle mode oractive mode. As mentioned above, there are at least two situations, inaccordance with this disclosure, that the battery longevity may beimproved in the event that communication over an alternative network isavailable. In idle mode, where it's determined that battery power levelhas dropped to a predetermined threshold while operating pursuant to afirst communication protocol, the device switches to operation pursuantto a second communication protocol. Also, in active mode, where it'sdetermined that battery power level has dropped to a predeterminedthreshold while operating pursuant to a first communication protocol,the device switches to operation pursuant to a second communicationprotocol.

In some embodiments, in active mode, a cellular communication may costmore than a WIFI communication. Therefore, it may be more cost effectiveto maintain communication with a WIFI service when possible due to airtime fees. However, once a call over the WIFI service is completed, thedevice may operate pursuant to the WIFI protocol while in an idle mode.When the device operates pursuant to the WIFI protocol in idle mode, thedrain on the battery power level can be greater than were the device tooperate pursuant to a cellular communication protocol.

FIG. 2 is a flow chart illustrating the operation of a mobilecommunication device in idle mode. As described above, the device mayoperate pursuant to a first protocol 202, here a WIFI protocol, while inidle mode. More generally, however, the first protocol may be any othercommunication protocol. The battery level of the device may be monitored204, periodically or constantly. At 206, a query is made to determinewhether the battery power level has dropped to a predeterminedthreshold. If there is no determination that the battery power level hasdropped to a predetermined threshold while operating pursuant to thefirst communication protocol, here a WIFI protocol, in idle mode, thedevice maintain its operation in pursuant to the first protocol 208.

FIG. 2 further illustrates that when in idle mode and operating pursuantto the first protocol, the device can determine if the device is in anemergency call situation 210. In such an event, the device may notswitch from the first communication protocol to the second communicationprotocol in the event that the battery power level drops to thepredetermined threshold. Accordingly, the device may maintain the statusquo 212. For example, if the battery-powered multimode wirelesscommunication device were in an emergency call situation, an emergencyservice provider such as the police or fire department may receive themobile communication device's telephone number by, for example, a callerID, and may try to return a call to the mobile communication device. Inan emergency call situation, it may be beneficial that during anemergency call back period, the mobile communication device should beable to receive a callback from the Public Safety Answering Point (PSAP)pursuant to the same communication protocol from which the call wasmade.

Therefore when the battery power level drops to a predeterminedthreshold, there may be sufficient battery usability to sustain a shortcellular call during an emergency callback period. Once the batteryreaches this state, the device may indicate, for example, on itsdisplay, that multimedia and other battery intensive operations shouldbe avoided. Alternatively, the device may automatically shut downancillary activity. The predetermined battery power threshold can becalibrated to sustain the power necessary to receive a callback during acallback period, or may be calibrated according to a different standard.

After the query of the battery power level while in idle mode, thedevice operating pursuant to the first protocol, here, a WIFI networkprotocol, may begin scanning for service pursuant to a second protocol,here, a cellular network in the event that the battery power level hasdropped to the predetermined threshold 214. The device may then switchfrom the first wireless communication protocol so that the device canoperate in accordance with the second communication protocol 216 in theevent that the battery power level has dropped to the predeterminedthreshold in idle mode. Accordingly, some battery usability may beprolonged.

FIG. 3 is a flow chart illustrating operation of a mobile communicationdevice in active mode. As described above, the device may be operatingpursuant to a first protocol 302, here a cellular communication protocolwhile in an active mode. The battery level of the device may bemonitored 304 periodically or constantly. A query can be made whetherthe battery power level has dropped to a predetermined threshold 306. Ifthere is no determination that the battery power level has dropped to apredetermined threshold while operating pursuant to the firstcommunication protocol, here a cellular protocol, in an active mode, thedevice can maintain its operation pursuant to the first protocol 308.

The switch in either the idle mode or the active mode can be madeautomatically or by response of the user to a prompt of the device. InFIG. 1, the battery icon 110 on the display may provide an indicationthat the switch from a first communication protocol to a secondcommunication protocol may be made. It is understood that any type ofprompt to switch protocols when the battery power drops to apredetermined level is within the scope of this discussion.

FIG. 3 further shows that when in active mode and operating pursuant tothe first protocol, the device can determine if the device is in anemergency callback situation 310. In the event that the battery powerlevel drops to the predetermined threshold during an emergency call, thedevice does not switch from the first communication protocol to thesecond protocol. Accordingly, the device may maintain the status quo 312when in an emergency callback situation.

After the query for the battery power level in active mode, the deviceoperating pursuant to the first protocol, here, cellular networkprotocol, begins scanning for service pursuant to a second protocol,here, a WIFI network protocol in the event that the battery power levelhas dropped to the predetermined threshold 314. The device then switchesfrom the first wireless communication protocol so that the device isoperating in accordance with the second communication protocol 316 inthe event that the battery power level has dropped to the predeterminedthreshold while operating pursuant to the first communication protocolin active mode. Accordingly, the battery usability may be prolonged.

The scan rate may also be based on the battery power level. In the eventthe battery power level has dropped to a predetermined threshold, thatis the same as that which is described above, or different from thatwhich is described above, the scan rate for service pursuant to a secondprotocol may be slowed to conserve power.

FIG. 4 is a signal flow diagram of a mobile communication device in idlemode. The device 402, the WLAN access point 404 and the cellular network406 are depicted therein. The device can be in an idle state pursuant toa first communication protocol, in this example, a cellular networkprotocol 408. The device can perform a background scan for a WIFI accesspoint 410 to establish communication under a second protocol, in thisexample, a WIFI communication protocol. If the WIFI access point isfound, there may be a switch from the cellular network to the WIFIaccess point when the device is in the idle state 412. However, in theevent that the battery power level drops to a determined threshold level414, the device can switch in its idle state so that it is operatingpursuant to a cellular communication protocol 416. Accordingly, batteryusability may be prolonged.

FIG. 5 is a signal flow diagram of a mobile communication device inactive mode. The device 502, the WLAN access point 504 and the cellularnetwork 506 are depicted therein. A cellular network call is in progressat 508. At 510, the device may perform a background scan to see if WIFIis available. If available, wherein WIFI is the preferred mode 512,there is a hand-off to the WIFI access point of a call in progress 514.If it is determined that the battery power level has dropped to apredetermined threshold level 516, the active call state can remain withthe WIFI access point 518 since the WIFI communication protocol can havea better battery in-call performance than does a call over a cellularnetwork. Accordingly, the battery usability may be prolonged.

Since it has been found that in an idle state, less power is consumedwhen operating pursuant to a cellular communication protocol than whenoperating pursuant to a WIFI communication protocol, the device mayincrease its longevity based on current battery consumption if thedevice were to switch from the more consumptive to the less consumptivecommunication protocols. The same can be true in the active state,though the relationship is reversed.

While the present disclosure and the best modes thereof have beendescribed in a manner establishing possession by the inventors andenabling those of ordinary skill in the art to make and use the same, itwill be understood and appreciated that there are equivalents to theexemplary embodiments disclosed herein and that modifications andvariations may be made thereto without departing from the scope andspirit of the inventions, which are to be limited not by the exemplaryembodiments but by the appended claims.

What is claimed is: 1-20. (canceled)
 21. A method in a battery-poweredmultimode wireless communication device that operates pursuant to afirst active communication mode and to a second active communicationmode, the method comprising: running, on the wireless communicationdevice, a first function and a second function; determining whether abattery-power level has dropped to a predetermined threshold whileoperating pursuant to the first active communication mode; and if thebattery-power level drops to the predetermined threshold while operatingpursuant to the first active communication mode, then switching fromoperation of the wireless communication device in the first activecommunication mode to operation in the second active communication modefor the first function while continuing to operate in the first activecommunication mode for the second function.
 22. The method of claim 21wherein the first and second functions are selected from the groupconsisting of: a video streaming function and a voice calling function.23. The method of claim 21 wherein switching from the first activecommunication mode includes switching from operation on a cellularcommunication protocol to operation on a wireless local area networkprotocol.
 24. The method of claim 21 wherein switching from the firstactive communication mode includes handing off a third function runningon the wireless communication device to an external device.
 25. Abattery-powered multimode wireless communication device that operatespursuant to a first active communication mode and to a second activecommunication mode, the wireless communication device comprising: aprocessor that runs a first function and a second function; abattery-power level determination module coupled to a battery; and aswitching module that, if the battery-power level drops to apredetermined threshold while operating pursuant to the first activecommunication mode, switches from operation of the wirelesscommunication device in the first active communication mode to operationin the second active communication mode for the first function whilecontinuing to operate in the first active communication mode for thesecond function.
 26. The method of claim 25 wherein the first and secondfunctions are selected from the group consisting of: a video streamingfunction and a voice calling function.
 27. The method of claim 25wherein switching from the first active communication mode includesswitching from operation on a cellular communication protocol tooperation on a wireless local area network protocol.
 28. The method ofclaim 25 wherein switching from the first active communication modeincludes handing off a third function running on the wirelesscommunication device to an external device.